1. Field of the Invention
This invention relates to the erection of outdoor signs or other elevated structures that are mounted on poles or posts. This invention also relates to truck mounted cranes in which earth boring bits can be transported on the truck and are attachable to the crane for boring holes in which the poles or posts are to be anchored.
2. Description of the Prior Art
Commercial truck mounted cranes with hydraulic booms are typically employed to erect large outdoor signs having a height of four feet or greater. These signs are commonly employed in front of commercial establishments, and their height allows potential customers to easily identify the business or its location. Since these signs are erected on site it is necessary to employ mobile trucks with cranes to erect the signs. However, conventional crane mounted trucks do not have the capability of performing all of the tasks needed to erect these signs. One critical shortcoming is that conventional truck mounted cranes cannot be employed to drill the holes in the earth or in pavement in which these signs will be erected. Normal practice requires the use of a separate vehicle, such as a line truck, that is equipped with a earth boring bit of the type suitable for drilling these holes. Since the site at which the sign is to be located may be remote from the facilities of an operator of a commercial truck mounted crane, it is often necessary to secure the services of a local contractor, with appropriate equipment, to drill the necessary holes. Quite often this can result in a significant delay for the operator of the truck mounted crane, especially when the site may be in a different state or can be quite remote from his facilities. The crane operator is then at the mercy of other contractors, with whom he may not be familiar, or who may have a significant backlog. This can result in significant delays and add significant cost.
U.S. Pat. No. 6,533,048 discloses an earth boring bit driven by a hydraulic motor which is connected to a boom on a mobile machine or vehicle. This earth boring bit includes a cylindrical drum in which earth or other debris from a bored hole is retained as rotating cutting teeth on the base of the drum cut into the earth or pavement. This drum serves to collect the debris, which can then be removed from the hole to a neighboring collection point or container. When the bit has been moved to the collection location by rotation of the boom on which it is mounted, the base of the drum can be allowed to swing open, emptying the debris removed from the hole. This earth boring bit can be used instead of augers or other boring bits, which require a separate implement to remove earth or other debris from the bored hole. This earth boring bit can be used on a vehicle with a swinging hydraulic boom or on tractors, skid steer backhoes or other mobile machines or vehicles having a stationary boom. This earth boring bit is intended for use on line trucks or other equipment that is normally used at least in part for earth moving operations, such as drilling holes, and includes a hydraulic system having sufficient capacity for operating the earth boring bit. In particular, this earth boring bit is intended for use with vehicles having a boom capable of delivering sufficient hydraulic fluid to the hydraulic motor suspended from the end of the boom above this earth boring bit.